Microfluidic device micromixer

Recently, a similar approach based on isotachophoresis was reported in a microfluidic device, demonstrating its usefulness for micromixing purposes [ 170]. The author demonstrated that a small sample volume could be brought in contact in a controllable manner to trigger a fairly fast mixing. This type of mixer does not require comphcated geometry and could be particular useful in the field of digital microfluidics. 

Micromixing Within Microfluidic Devices rotating raswvoire... 

Typically, microfluidic devices have channels with dimensions between 10 and 400 pm. This small dimension compared to conventional mixing systems results in an increase in the surface-to-volume ratio, to 10,000-50,000 m m compared with 100-2,000 m m of their macroscale counterparts. This characteristic endows micromixers with a superior heat transfer and control [192], allowing reactions to be performed in an isothermal manner [83, 193, 194]. Due to their heat transfer efficiency, micromixers can be conveniently applied for handling reactions in which fast heating and cooling of the reaction mixture are required, such as highly exothermal reactions [9, 195-199]. 

Owing to the excellent capability of microfluidic devices and the presence of micromixer technology that has been studied in depth, it can be anticipated that in the near future more practical laboratory and industrial applications for micromixers will be developed. 

The term active mixer or active micromixer refers to a microfluidic device in which species mixing is enhanced by the application of some form of external energy disturbance. Typically, this disturbance is generated either by moving... 

A passive micromixer is one of the microfluidic devices. It utilizes no energy input except the mechanism (pressure head) used to drive the fluid flow at a constant rate. Due to the dominating laminar flow on the microscale, mixing in passive micromixers relies mainly on chaotic advection realized by manipulating the laminar flow in microchannels or molecular diffusion with increasing the contact surface and time between the different fluid flows. 

Swickrath MJ, Bums SD, Wnek GE (2009) Modulating passive micromixing in 2D microfluidic devices via discontinuities in surface energy. Sens Actuators B 140(2) 656-662... 

In addition to the determination of the fluid velocity in microcharmels, there have been recent developments in scalar-based visualization methods for micromixers. The use of regular fluorophores such as fluorescein or Rhodamine B is very common in direct visualization of mixing in microfluidic devices. 

Optimizing the efficiency of droplet formation, disintegration and stabilization is the domain of microengineered devices. Here, micromixers, optimized high-pressure homogenizer nozzles and specific microfluidic devices such as microchannels are under investigation. 

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